A Heat Transfer Textbook - EME Technologies

1 A heat Transfer TextbookA heat Transfer TextbookF o u r t h E d i t i o nbyJohn H. Lienhard IVandJohn H. Lienhard VPhlogistonPressCambridgeMassachusettsPr ofessor John H. Lienhard IVDepartment of Mechanical EngineeringUniversity of Houston4800 Calhoun RoadHouston TX 77204-4792 John H. Lienhard VDepartment of Mechanical EngineeringMassachusetts Institute of Technology77 Massachusetts AvenueCambridge MA 02139-4307 2017 by John H. Lienhard IV and John H. Lienhard VAll rights reservedPlease note that this material is copyrighted under Copyright Law. Theauthors grant you the right to download and print it for your personal use orfor non-profit instructional use. Any other use, including copying, distributingor modifying the work for commercial purposes, is subject to the restrictionsof Copyright Law. International copyright is subject to the BerneInternational Copyright authors have used their best efforts to ensure the accuracy of the methods,equations, and data described in this book, but they do not guarantee them forany particular purpose.

2 The authors and publisher offer no warranties orrepresentations, nor do they accept any liabilities with respect to the use ofthis information. Please report any errata to the , John H., 1930 A heat Transfer Textbook / John H. Lienhard IV andJohn H. Lienhard V 4th ed. Cambridge, MA :Phlogiston Press, c2017 Includes bibliographic references and heat Transmission 2. Mass TransferI. Lienhard, John H., V, 1961 II. 2017 Published by Phlogiston PressCambridge, Massachusetts, book was typeset in Lucida Bright and Lucida New Math fonts (designed byBigelow & Holmes) using LATEX under the TEXShop updates and information, visit: copy is:Version dated 17 July 2017 PrefaceWe set out to write clearly and accurately about heat Transfer in the 19811stedition ofA heat Transfer Textbook . Now, this 4thedition embodies allwe have learned about how best to do that. Whether one studies alone orwith a class, learning means posing, then answering, one s own want students to find their Oh, now I see!

3 1stedition went through many printings. A 2ndedition followedin 1987; and John H. Lienhard V, who had done some work on the 1stedition, then added a new chapter on mass Transfer . That edition wentthrough more printings before the book briefly went out of decided, in the late 1990s, to create a new free-of-charge, 3rdedition for the Internet. The notion of an ebook was then entirely new and not fully accepted! The Dell Star Program funded the major updatingand recoding of the text. That 3rdedition became a part of MIT s newOpenCourseWare initiative, in 2000. (We also put out several paperbackversions of the 3rdedition through Phlogiston Press.) Many successiverevisions updated and improved the on-line version. By 2010, the texthad changed greatly, and we declared it to be a 4thedition. People onevery continent, and in almost every country, had downloaded it a quartermillion times by then. Dover Publications now offers the 2011 4theditionin a low-cost hard copy.

4 But we keep correcting, updating, and editingthe ebook book is meant for juniors, seniors, and first-year graduate studentsas they learn conduction, convection, radiation, phase-change, and therelated subject of mass Transfer . It is designed to serve different levelsdepending on how instructors (or independent students) use it. Eachpart begins simply. Then it moves into more sophisticated may choose not to cover all that later , and care to get things right and complete, remain our guidingaims. We take care to deal with implications, limitations, and includes connecting the subject to the real world that it serves. Itmeans developing insight into heat Transfer subject is meaningful only if students stay grounded in real-worldissues. So we begin with a three-chapter introduction to conduction,convection and radiation. Then we treat the use and design of heatexchangers. Students with that background find far more meaning inlater and more complex material.

5 Those first three chapters providebackground they will need through the rest of the earlier parts of subsequent chapters also provide ideas that weuse in chapters that follow. The later parts might not be needed dimensional analysis: We develop it in a new way, early in Chapter4. Then we use that approach throughout the book. But later chapters donot need the important and useful material on fin design, at the end ofChapter , we mention our strong belief that the challenges of applyinga knowledge of heat Transfer must be met with an understanding ofunderlying concepts beyond specific equations and methods alone. Wetherefore lay more than the usual stress on these concepts, not just inthe text, but in the end-of-chapter problems as owe thanks to many people. Our colleagues and students at MIT,the University of Houston, the University of Kentucky, and elsewhere haveprovided suggestions, advice, and corrections.

6 We are especially gratefulto the many thousands of people worldwide who have emailed us withthanks, ideas, and encouragement to continue this IV, University of HoustonJHL V, Massachusetts Institute of TechnologyJuly 2017 ContentsPrefacevI The General Problem of heat Exchange11 Transfer .. of heat Transfer to thermodynamics .. of heat Transfer .. look ahead .. the end-of-chapter problems ..35 Problems ..37 References ..472 heat conduction concepts, thermal resistance, and the overallheat Transfer heat diffusion equation .. of the heat diffusion equation .. resistance and the electrical analogy .. heat Transfer coefficient,U..87 Problems ..88 References ..983 heat exchanger and configuration of heat exchangers .. of the mean temperature difference in a heatexchanger .. exchanger effectiveness .. exchanger design .. 128 Problems .. 131 References .. 138II Analysis of heat Conduction1414 Analysis of heat conduction and some steady well-posed problem.

7 General solution .. analysis .. illustration of dimensional analysis in a complexsteady conduction problem .. design .. 165 Problems .. 186 References .. 1935 Transient and multidimensional heat .. solutions .. conduction in a one-dimensional slab .. charts .. solutions .. heat conduction to a semi-infinite region .. multidimensional heat conduction .. multidimensional heat conduction .. 249 Problems .. 254 References .. 266 III Convective heat Transfer2696 Laminar and turbulent boundary introductory ideas .. incompressible boundary layer on a flat surface energy equation .. Prandtl number and the boundary layer Transfer coefficient for laminar, incompressible flowover a flat surface .. Reynolds analogy .. boundary layers .. Transfer in turbulent boundary layers .. 323 Problems .. 332 References.

8 3397 Forced convection in a variety of .. Transfer to and from laminar flows in pipes .. pipe flow .. Transfer surface viewed as a heat exchanger .. Transfer coefficients for noncircular ducts .. Transfer during cross flow over cylinders .. configurations .. 386 Problems .. 388 References .. 3968 Natural convection in single-phase fluids and during .. nature of the problems of film condensation and ofnatural convection .. natural convection on a vertical isothermalsurface .. convection in other situations .. condensation .. 431 Problems .. 446 References .. 4559 heat Transfer in boiling and other phase-change configurations s experiment and the pool boiling curve .. boiling .. pool boiling heat flux .. boiling .. heat flux .. boiling and system influences .. convection boiling in tubes .. convective condensation heat Transfer .

9 Condensation .. The heat pipe .. 512 Problems .. 515 References .. 520xContentsIV Thermal Radiation heat Transfer52710 Radiative heat The problem of radiative exchange .. Kirchhoff s law .. Radiant heat exchange between two finite black bodies . heat Transfer among gray bodies .. Gaseous radiation .. Solar energy .. 578 Problems .. 588 References .. 596V Mass Transfer59911 An introduction to mass Introduction .. Mixture compositions and species fluxes .. Diffusion fluxes and Fick s law .. Transport properties of mixtures .. The equation of species conservation .. Mass Transfer at low rates .. Steady mass Transfer with counterdiffusion .. Mass Transfer coefficients at high rates of mass Transfer . Simultaneous heat and mass Transfer .. 666 Problems .. 676 References .. 690VI Appendices693A Some thermophysical properties of selected materials695 References.

10 698B Units and conversion factors725 References .. 729C Nomenclature731 VII Indices739 Citation Index741 Subject Index747 Part IThe General Problem of HeatExchange11. IntroductionThe radiation of the sun in which the planet is incessantly plunged,penetrates the air, the earth, and the waters; its elements are divided,change direction in every way, and, penetrating the mass of the globe, wouldraise its temperature more and more, if the heat acquired were not exactlybalanced by that which escapes in rays from all points of the surface andexpands through the Analytical Theory of heat ,J. heat transferPeople have always understood that something flows from hot objectsto cold ones. We call that of the late eighteenthcentury finally decided that all bodies must contain an invisible fluidwhich they was assigned a variety of properties,some of which proved to be inconsistent with nature ( , it had weightand it could not be created nor destroyed).